Caster for robot

ABSTRACT

When a solid such as a utensil or a structure thing moves, stability is high, it is suitable for the indoor use, furthermore to provide the caster which can use the foot part of robot walking by the two pairs. A caster is comprised of a rocking shaft which sets up a wheel, a stably supporting leg, a slidably stabilizing plate and wheel, a drive device which rocks a rocking shaft and change an angle of a slidably stabilizing plate, the detection device which detects a change in the angle and the detection devices which detect a change in the increased weight. And stability is higher than the existent caster, the caster with sled for getting over obstacles which can brake without controlling the movement of the wheel of the existent caster and the axle which holds a wheel by the mechanism such as the brake for braking, in other words, a caster for the robot can be made.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This is a continuation application of U.S. patent application No. 09/423,169, filed Nov. 2, 1999, which is the United States National Phase under 35 U.S.C. §371 of International Application PCT/JP99/01085, filed Mar. 5, 1999, which claims priority to Japanese Patent Application No. 10/98084, filed Mar. 6, 1998. The disclosure of the United States patent application and the International Application is herein incorporated by reference in its entirety. The International Application was not published under PCT Article 21(2) in English.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] This invention improves a caster with a sled for moving over a surface of varying height. The new caster size is smaller than the size of the existent caster since larger wheels are limited by the space.

[0004] If the existing caster is moved by a person or moves freely it is unable to travel over an obstacle of varying height along its transit plane.

[0005] This invention is for a caster that has higher stability than the existent caster whose movement can be controlled without the use of a brake to the wheel and a wheel's axle.

[0006] In other words, this is the invention of a caster for a robot.

[0007] And this is the invention of a caster for a robot with a foot part of the robot walking by the two pairs, because of a caster with the sled for traveling over obstacles can stand on itself, by maintaining stabilization by one caster with a sled for traveling over obstacles or two.

[0008] 2. Description of the Related Art

[0009] So far, when any object, such as a utensil or a structure is moved, there was a caster used as a means that a wheel met the transit plane.

[0010] The caster was usually used with more than two wheels because the caster could not secure a load by standing on one wheel or two wheels, and one wheel or two wheels used it when it was based on the use of the centrifugal force.

[0011] When the existent caster is not available because of an obstacle in the path of its transit plane, obstacles such as a utensil or a structure are being moved, the existent caster that has a big wheel and the big wheel installed directly in the object were used for traveling over obstacles.

[0012] When a big wheel isn't available for the surrounding conditions the existent caster couldn't travel over obstacles with the little wheel.

[0013] Though sled friction was high, when it is used under conditions like touching the snow of friction was little, it was hard to use in the building because of frictional resistance with the floor was too high.

[0014] When a caster is attached to the robot and used, many little wheels were set up and continued for securing stability and the form of the caterpillar were used.

[0015] Furthermore we used by three legs for the foot part or more than two wheels when use in two wheels was difficult.

[0016] This applicant has applied for the invention of the walker that installed the caster and kept a plate at the bottom of the frame body under Japanese patent application JP 7-236670.

[0017] It is an example to correct the above mentioned inconvenient in order to move with stability inside a building that has an abundance of traversing obstacles such as the edge of a TATAMI mat or some other type of material.

[0018] Especially it is the invention to correct the inconvenient that a handicapped person fall down due to the rotation of the wheels and to be able to traverse a surface such as steps at the time of using a walker at home.

[0019] And this applicant has applied for the caster of which a plate for traveling over a step with stability was kept as Japanese patent application JP 9-92722.

[0020] And this applicant has applied for the caster that has a plate of which, the gross touching area to the ground is variable due to the adjustable movement of a plate back and forth, up and down and a change in an angle as Japanese patent application JP 10-98084, based on Japanese patent application JP 9-92722 as a domestic priority.

[0021] There is JP 64-44301's official report as an example of the existent caster.

[0022] When this caster rolls over a flat surface in the same manner as the existing caster its purpose is to assist the existing caster to travel over steps that obstruct it by keeping only the sled in front of the caster.

[0023] And the purpose of it is to control of the proceeding direction of a sled and a caster into the proceeding direction in order that traveling over a step may not become impossible by pivoting of the caster.

[0024] At the same time, the realization is attempted by the stopper that secures a sled material to be set up in order to run with rolling on top of the flat surface of the road.

[0025] The purpose of JP 64-44301's official report is as mentioned above, then it is mentioned in the embodiment that the drive power is kept by the other wheel that isn't mentioned in FIG. 1 of quotation example 2.

[0026] In comparison with the caster in the request of Japanese Utility Model Application 64-44301's official report, this invention enhances stability by establishing the gross touching area of a plate to the ground.

[0027] And it is an invention in order to control the acceleration of the caster by making friction variable because of making the gross touching area to the ground change.

[0028] And it is invention to be able to stand on a caster by itself because stability is enhanced by changing the loading point as the wheel moves.

[0029] And there is the request of Japanese Utility Model Application 50-140166's official report as an example of the existent caster.

[0030] But it is composed of the link where it is attached to the bottom of the weight body, a wheel attached to the middle part of the link and the fixing device that fixes the end of others on the bottom with an adjustable distance.

[0031] When FIG. 1 of the official report and all the figures from FIG. 4 to FIG. 6 that show an embodiment being examined, it is considered that the caster of the request of Japanese Utility Model Application 50-140166's official report its aims at lifting the weight body to the height desired.

[0032] The caster of Japanese Utility Model Application 50-140166 is combined with other structures and the stability is enhanced, securing high stability by independently adjusting the height of each individual wheel.

[0033] This invention enhanced stability by making a plate that is designed for the gross touching area to the ground.

[0034] It controls the acceleration of the caster by changing the gross touching area to the ground.

[0035] In other words it controls the acceleration by the change in pressure of the part of a plate that touches the ground.

[0036] In other words it controls the acceleration by changing the form of the touching part of a plate to the ground.

[0037] Additionally it enhances stability by changing the loading point of a wheel due to a front and back motion while maintaining its function as a wheel.

[0038] In comparison with the caster in request Japanese Utility Model Application 50-140166, this invention is a totally different idea.

[0039] This is a new invention due to the fact that it is able to support a structure with a single wheel and provide motion of a structure due to its high stability.

[0040] In this inventors application of JP 7-236670 the hole in the plate enables a rotating wheel's surface to easily touch the floor.

[0041] Therefore the movement of the walker as well as a person's movement is made smoother due to the wheel reducing the friction between a plate and the floor.

[0042] As mentioned above, the wheel's surface easily touches the floor.

[0043] There is neither idea of the front and back movement nor the up and down movement of the wheel.

[0044] There is no idea to control the change of acceleration by making the gross touching area of the plate to the ground adjustable due to the movement of the wheel's position.

[0045] There are descriptions that a part of the plate, which can touch the ground at the bottom, is shaped and the inconvenience that any change in direction or side movement cannot be performed easily due to excessive friction was eliminated.

[0046] However, there is neither way to control the friction nor the change of variable acceleration by adjusting the gross touching area of the plate to the ground.

[0047] This invention realizes as new ideas, the following characteristics:

[0048] It can control acceleration by making friction variable due to its ability to make the gross touching area to the ground of a plate adjustable.

[0049] And then, in the condition that an angle of inclination of a plate is unchanged, friction of the plate to the ground area is controlled to change in the condition that the plate and a wheel are touching the ground area.

[0050] And then it is able to change the contact pressure of the ground to the plate into the condition that a wheel doesn't touch the ground area due to the change of an angle of inclination of the plate.

[0051] Also it is able to assemble the propulsion device that is able to make the angle of inclination of the plate change.

[0052] If an angle of inclination of the plate is changed, it is detected by a detection device.

[0053] It outputs detection data for detecting changes in an angle of inclination of the plate.

SUMMARY OF THE INVENTION

[0054] This invention is composed of a plate that can change an angle of inclination, a supporting leg structure that composed on a plate, a rocking shaft that connects to a wheel and an upper object and can rock in the space from the front to the back on the plate with an angle of inclination and a wheel.

[0055] The plate could be shaped by a material that has a flexible quality.

[0056] And the gross touching area of the plate to the ground can be changed when the plate has a flexible quality.

[0057] And also a friction material can be set up in a plate.

[0058] The friction can be varied due to the friction material.

[0059] A touching pressure to a ground that a touching part to the ground of the plate receives can be varied.

[0060] It is possible to maintain a propulsion device that can change an angle of inclination of this plate.

[0061] And it is possible to maintain a detection device for an angle of inclination of this plate changing.

[0062] And it is possible to output detection data detected by the detection device for changes in an angle of inclination of the plate.

[0063] The rocking shaft can rock front to back in a space on a plate and be assembled a propulsion device that can change an angle appearing to turn a rocking shaft.

[0064] The rocking shaft can maintain a detection device of the rocking shaft rocking and output detection data.

[0065] The wheel that is arranged in a hole that is established in the plate can be moved in this hole in the front and back direction and also in the up and down direction.

[0066] It is possible that either of the first flange on the tip side and the second up side flange on the aft side of the plate mentioned above is shaped.

[0067] It is possible that the first flange is shaped approximately ⅓ of the entire length of the plate and the second up side flange can be shaped by a smaller radius than the first flange.

[0068] The plate is able to maintain an angle of inclination in the left to right direction and to shape an angle of inclination that can be changed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0069]FIG. 1 is a desirable caster for a robot; namely it is a side view that shows substantial parts of the first embodiment.

[0070]FIG. 2 is a slope figure that shows substantial parts in the same way.

[0071]FIG. 3 is a ground plan that shows substantial parts in the same way.

[0072]FIG. 4 is a rear figure that shows substantial parts in the same way.

[0073]FIG. 5 is the A-A′ cross section that is shown in FIG. 4.

[0074]FIG. 6-1, FIG. 6-2 and FIG. 6-3 are side views that show the conditions of a plate that touch the ground for the explanation.

[0075]FIG. 7-1 and FIG. 7-2 are side views that show the conditions of the touching part to the ground of the wheel for the explanation.

[0076]FIG. 8-1 and FIG. 8-2 are rear figures that show the conditions of the touching part of the plate to the ground for the explanation.

[0077]FIG. 9 is a reference figure of this invention, which shows an opening for friction of a plate and also shows a part of the friction material.

[0078]FIG. 10 is a side view that shows substantial parts of the desirable caster for the robot in the other embodiment of this invention.

[0079]FIG. 11 is a slope figure that shows substantial parts in the other embodiment in the same way.

[0080] It is the side view that shows the second embodiment of this invention.

[0081]FIG. 12 is a general idea of how to compute the wheel size by measuring the distance between two points of which the part that touches the ground of a big wheel and the first point to touch an obstacle are presumed.

[0082]FIG. 13 is a control circuit in the first embodiment.

[0083]FIG. 14 is a flow chart when the connections of a propulsion device and a plate and a propulsion device and a rocking shaft are being cut in the first embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0084] The inventor describes the first embodiment that is a desirable caster for a robot in accordance with figures attached from FIG. 1 to FIG. 9 and from FIG. 12 to FIG. 14 in order to describe this invention in detail.

[0085] A plate (1) is used and materials are shaped such as strong plastics, metals and other materials.

[0086] For this description the word “plate (1)” shall be used to mean “plate (1).”

[0087] And the plate (1) has the first flange (1 a), which the tip side is raised in a big bend radius (R) to roughly ⅓ of the entire length and it has the second up side flange (1 b), which has a bend radius (R′) that is a smaller bend radius than the first flange (1 a) in the aft side.

[0088] And the first flange (1 a) is shaped under the condition that it is rising from a transit plane (g) based on the touching part to the ground (1 c) of the plate (1).

[0089] And then the plate (1) is shaped and raised in the back from the touching part to the ground (1 c) by various degrees of an angle of inclination to the back (K) by roughly an angle of three degrees for example.

[0090] In this embodiment, an arch (4) of which the center is a point of a wheel that touches the ground (w) is roughly a semi-circle that made a distance to an arch upward supporting member (4 a) a radius.

[0091] And then it is the composition that can rotate freely to make an angle of the arch (4) change.

[0092] Then it is the composition that can rotate freely to make an angle of a shaft outside cover (3) change.

[0093] The plate (1) is shaped rotating around the point of the wheel that touches the ground (w) as a pivot as in FIG. 6-1, FIG. 6-2 and FIG. 6-3 are shown.

[0094] And though some degrees of an angle of inclination to the back (K) could be set up by the distance of the point of the wheel that touches the ground (w) and the touching part to the ground (1 c).

[0095] For example it was made roughly an angle of three degrees as for this embodiment.

[0096] This angle is to replace the effect of a big wheel in that FIG. 12 shows depending on the distance from the point of the wheel that touches the ground (w) to the rear touching part to the ground (1 c′) and the height of the wheel in FIG. 6-2 shown.

[0097] And it is good if the touching part to the ground (1 c) or the rear touching part to the ground (1 c′) is set up as a fixed angle in order to control the speed by the pressure due to changing an angle of a plate.

[0098] When a plate touches the ground, a wheel rises from the ground due to a much stronger rotation pressure applied to the plate being increased, so that all the driving force of the wheel becomes zero.

[0099] Therefore it means the pressure and/or the friction at the touching part to the ground (1 c) dictates the strength of the braking power.

[0100] Though it isn't illustrated, it is the same as for the rear touching part to the ground (1 c′) as well.

[0101] Especially FIG. 6-3 as an assumption figure that pulled up a wheel after a plate became parallel to a transit plane, therefore the stability in proportion to the size of the area at the bottom of a plate is provided.

[0102] The braking of a caster becomes possible by changing an angle of a plate in this way.

[0103]FIG. 7-1 and FIG. 7-2 show the condition that a rocking shaft rocks.

[0104] They show the position of a wheel that can be changed in front and back depending on the rocking of a rocking shaft when shaft-cover connecting screws (4 d 1, 4 d 2) were made in the center of rocking.

[0105] When the wheel was further moved from the touching point of the ground of the wheel (p) that was located under the sloped rocking shaft by the movement in front and back depending on rocking a rocking shaft, the space (s) between the part that touches the ground of the wheel under the sloped rocking shaft and the point of the part that touches the ground of the wheel moved is displayed as shown in FIG. 7-1.

[0106] By this, when rotation pressure is increased much more to a rocking shaft, a wheel rises.

[0107] Therefore all the driving force by a wheel becomes zero.

[0108] The pressure in the touching part to the ground (1 c) and/or friction prescribes the strength of the braking power.

[0109] And also an up-down movement of a rocking shaft or a wheel is necessary so that the point that touches the ground of the wheel (Q), which moved under a sloped rocking shaft that was located by the movement in front and back caused by rocking of a rocking shaft from the touching point of the ground of the wheel (p) under the sloped rocking shaft that touches the ground.

[0110] A loading point by rocking of a rocking shaft can be moved between the touching point of the ground of the wheel (p), under a sloped rocking shaft and the touching part to the ground (1 c), like loading shaft (f) and loading shaft moved (f) show as FIG. 7-2.

[0111] As for this embodiment, though it isn't shown, a movement of the loading point is detected and it can be outputted.

[0112] Even if a wheel is being fixed in a part that touches the point of the wheel that touches the ground (w) that is shown in FIG. 6-1, FIG. 6-2 and FIG. 6-3, a loading point can be moved between the point of the wheel that touches the ground (w) under a sloped rocking shaft and the touching part to the ground (1 c).

[0113] And also a plate (1) is shaped roughly the size of the width 10 cm, the length 28 cm and a thickness 5 mm due to planning for the stability of the movement.

[0114] A hole (1 w) is maintained roughly in the center of the bottom of a plate (1) so that the bottom of a wheel (2) touches the ground at the point of the wheel that touches the ground (w).

[0115] The wheel (2), which is maintained by using an axle (2 a) with a shaft outside cover (3) that maintains free rotation in an arch (4) goes through the hole (1 w).

[0116] An arch end-supporting member (1 e) that is mid-air inside is set up near the upper surface of the first flange (1 a) and an arch end-supporting member (1 d) that is mid-air inside is set up near the upper surface of the second up side flange (1 b).

[0117] Both of the cases are maintained as a complete unit of a plate (1).

[0118] An opening (1 h), of which the size is such that the arch (4) can be swung right and left and is set up approximately in the center of the arch end-supporting member (1 e).

[0119] A cover (1 v) that is on either side of the arch end-supporting member (1 d) can be both opened and closed is set up.

[0120] An opening (1 g) is set up approximately in the center of an arch end-supporting member (1 d), whose size is such that the arch (4) can be swung right and left.

[0121] An arch (4) goes through an opening (1 h) in front and goes through an opening (1 g) in the back.

[0122] An arch (4) that went through an opening (1 g) is installed in a plate angle detection device (1 f).

[0123] And then an arch (4) is joined in left-right free rotation on the bottom of an arch end-supporting member (1 d), namely on the surface of a plate (1) and at an arch end contacting part (4 g).

[0124] An arch (4) that went through an opening (1 h) is joined in left-right free rotation at an arch end contacting part (4 h) and is joined to a load transducer (1Q) that is suspended from the top of an arch end-supporting member (1 e).

[0125] Both a battery storage compartment (1L) and a side to side adjustable motor (1 k) are set up in the arch end-supporting member (1 d).

[0126] The rotation by a side to side adjustable motor (1 k) is communicated to an arch end contacting part (4 g) and then moves a plate (1) up and down in a sideways motion. An angle of the plate (1) can be changed by the up and down sideways motion of the shaft (3 e) due to a plate (1) being rotated by a side to side adjustable motor (1 k) in the pivoting of both an arch end contacting part (4 g) and an arch end contacting part (4 h).

[0127] When there is no up-down movement of either the plate or a wheel in a caster for a robot, when it is located in a parallel position to a transit plane (g) due to changing an angle of the plate's (1) sideways motion, the plate (1) is designed such that a touching part to the ground (1 u) of the plate (1) can be configured as in FIG. 8-2 and shows from the condition of only a wheel touching the ground as an existent caster as in FIG. 8-1.

[0128] High stability can be maintained due to the side's entire length of the touching part to the ground (1 u) of a plate (1) touching the ground in FIG. 8-2.

[0129] Though the position of the wheel can change up and down in the first embodiment, even when it doesn't change up and down high stability can be maintained by to changing an angle of the plate (1) up and down and in a sideways motion like defined in both FIG. 8-1 and FIG. 8-2.

[0130] A friction material-supporting member (1R) is set up respectively on both sides (left-right position) of the arch end-supporting member (1 e).

[0131] And then by securing both sides to the friction material-supporting member (1R), the friction material (1 s) that goes through a bottom opening (1 p) and touches the ground at the touching part to the ground (1 c) of the plate (1).

[0132] The friction material (1 s) is molded in a half-circular arc-shape and uses such materials as a strong plastic, metal such as steel or other materials for example.

[0133] The length can be stored in the arch end-supporting member (1 e).

[0134] One side of a friction material (1 s) has the smooth surface where there is little friction.

[0135] And for example one other side of it is shaped by the part that has a file-shaped surface.

[0136] The variable friction part of the friction material (1 s) touches the ground through the bottom opening (1 p) gradually by rolling at the touching part to the ground (1 c).

[0137] When the strong frictional part of the friction material (1 s) touches the ground at the touching part to the ground (1 c), strong friction can be achieved and the speed is slowed down.

[0138] When the low friction part of the friction material (1 s) touches the ground at the touching part to the ground (1 c) it has minimal influence on the speed, due to a small amount of friction applied by the smooth surfaces that touch each other.

[0139] In this way changing the friction part of a friction material (1 s) can slow the speed down.

[0140] A friction material adjuster (1 t) is maintained by a friction material-supporting member (1R) and is a propulsion device that is made to turn a friction material (1 s).

[0141] As for this embodiment, the motor is used and electric power is supplied by a battery storage compartment (1L).

[0142] Any kind of propulsion device is good if the friction material (1 s) can be moved.

[0143] Though an arch end-supporting member (1 d) and an arch end-supporting member (1 e) were designed as a complete unit of a plate (1), it is also good that it is not all one complete unit.

[0144] A wheel (2) meets a transit plane (g) at the point of the wheel that touches the ground (w) of the wheel bottom.

[0145] The wheel (2) is supported by an arch (4), a shaft outside cover (3) and an axle (2 a) of the wheel (2) in the position where it went through the hole (1 w), and at the back side of the touching part to the ground (1 c) of a plate (1) positioned roughly at the bottom of the first flange (1 a) of a plate (1).

[0146] The shaft outside cover (3), a wheel (2) and an axle (2 a) can accommodate a motor, an engine and a drive mechanism such as a magnetic drive mechanism.

[0147] But, as for this invention, a battery (2 c) a motor (2 d) and a transmission mechanism (2 g) are being used.

[0148] And also it can be driven by external electrical power.

[0149] A shaft outside cover (3) is used and shaped from materials such as strong plastics, metals such as steel or other materials to assemble both a wheel (2) and an arch (4).

[0150] A shaft outside cover (3) is made a divided mid-air structure, in which parts can be stored and roughly a rectangle, is shaped with a strengthening plastic or metal and so on, is shaped by a material that can support the load of an object such as a utensil or a structure from a shaft (3 e) and is a structure that a plate (1) can be installed through an arch (4),

[0151] A battery (2 c), a motor (2 d), a transmission mechanism (2 g), a shaft angle detection device (2 b), a motor (2 w) that provides the power to change an angle of inclination of a plate (1) maintaining with an arch (4), an arch upward supporting member (4 a) that changes an angle of inclination of the plate (1) and an angle of inclination of a shaft outside cover (3) to the plate (1) according to make the arch (4) rotate by getting the power to change an angle of inclination of the plate (1) from a motor (2 w), an oil tank (4 c) for oil pressure by an oil pressure pump (2 e), a diaphragm (4 b) to go up and down caused by oil pressure from an oil pressure pump (2 e) with using oil from an oil tank (4 c), a shaft-cover connecting screws (4 d 1, 4 d 2) that joins the shaft outside cover (3) and the diaphragm (4 b) in order that a diaphragm (4 b) can be moved up-down, a control device (2 f), an arch downward supporting member (4 e) and an arch downward supporting member (4 f) can be stored in the shaft outside cover (3).

[0152] So that an arch (4) can go through, a hole (3 g) that size doesn't obstruct an up-down movement of the arch (4) is opened respectively in the front side and the rear side of the shaft outside cover (3).

[0153] And an up-down movement adjustment hole (3 a) is opened in the side of the shaft outside cover (3).

[0154] An outside information input terminal (3 b), an electric power jack (3 c) and an outside information output terminal (3 d) are shaped on the upper side of an up-down movement adjustment hole (3 a) of the shaft outside cover (3).

[0155] An arch downward supporting member (4 e) and an arch downward supporting member (4 f) keep the arch (4) in the moved position where it is rotated by the arch upward supporting member (4 a) and then to have changed a position by oil pressure to get from an oil pressure pump (2 e).

[0156] Though a strengthening rib (3 f) strengthens a shaft outside cover (3), it isn't necessary.

[0157] Though an electric power jack (3 c) is used to supply electric power in order to use a motor, it can be modified by any kind of a power source.

[0158] Though each of an outside information input terminal (3 b) and an outside information output terminal (3 d) sets up one jack for 2 lines, any form such as 10Base-T is good.

[0159] Though a function of the diaphragm (4 b), an arch downward supporting member (4 e) and an arch downward supporting member (4 f) are made possible by oil pressure, the capacity is variable such as water pressure or air pressure is good in order that the volume be adjustable.

[0160] Though the diaphragm moves up and down and is set in this embodiment, even when it doesn't move up and down, it is also possible that the device concerned with an up-down movement isn't installed, because the purpose of this invention can be made possible by changing pressure to a transit plane (g) of the plate (1) at the touching part to the ground (1 c).

[0161] For example, an arch (4) by using materials like strong plastics, metals such as a steel or other materials a circular arc that made a radius to an arch upward supporting member (4 a) as the point of the wheel that touches the ground (w) at a wheel's pivot point under the condition that a shaft (3 e) stands upright.

[0162] As for this embodiment, the arch (4) can rotate exactly therefore the inside of the perimeter makes a file-shaped form.

[0163] Anything is good if it can transmit the rotation of an arch upward supporting member (4 a) exactly such as a gear structure, a structure of a chain or other structure and then if it is a structure that can change an angle of inclination of the plate (1) and an angle of inclination of a shaft outside cover (3) toward the plate (1) that allows an arch (4) to move.

[0164] A control device (2 f) that is composed of a microcomputer inputs and outputs through a data transmission network (100).

[0165] An outside information input terminal (3 b), a shaft angle detection device (2 b), a plate angle detection device (1 f) and a load transducer (1Q) are connected with the data transmission network (100) on the input side.

[0166] And on the other hand an outside information output terminal (3 d), a friction material adjuster (1 t), a side to side adjustable motor (1 k), a motor (2 w), an arch upward supporting member (4 a), a motor (2 d), a transmission mechanism (2 g) and an oil pressure pump (2 e) connected with the data transmission network (100) on the as an output side.

[0167] A shaft angle detection device (2 b) uses an incline transducer.

[0168] A plate angle detection device (1 f) uses an incline transducer.

[0169] A load transducer (1Q) evaluates weight changes and when there is a change, the change is outputted.

[0170] Both a friction material adjuster (1 t) and a side to side adjustable motor (1 k) are motors.

[0171] Anything is good as a mechanism, so long as it can be driven.

[0172] A motor (2 w) and an arch upward supporting member (4 a) are configured to make an arch (4) rotate, therefore if an angle of an arch can be changed, a motor and a rotation transmission device can be designed to attach an outside housing and also a rotation transmission device can be attached to operate by hand.

[0173] A motor isn't necessarily needed.

[0174] A motor (2 d) and a transmission mechanism (2 g) are configured to drive a wheel (2), therefore these devices can be designed as attachments to an outside housing, but are not needed.

[0175] An oil pressure pump (2 e) is designed to make a diaphragm (4 b) move up and down by oil pressure and direct pressure to an arch downward supporting member (4 e) and an arch downward supporting member (4 f), but are not needed.

[0176] In the case, the top of an arch (4), an arch downward supporting member (4 e) and an arch downward supporting member (4 f) are structures that are easy to turn because of their smooth structure and also they can be secured while standing still, because there are both an arch downward supporting member (4 e) and an arch downward supporting member (4 f) at the top of an arch (4).

[0177] For example, an arch downward supporting member (4 e) and an arch downward supporting member (4 f) press down the top of an arch (4) powerfully by using a suspension type of spring.

[0178] Anything is good that an arch (4) is easy to turn and also a structure can be secured even when standing still.

[0179] The top of an arch (4), an arch downward supporting member (4 e) and an arch downward supporting member (4 f) are smooth structures, are easy to turn and also can be secured when standing still provided.

[0180] If an arch downward supporting member (4 e) and an arch downward supporting member (4 f) press down the top of an arch (4) powerfully by using a suspension spring and if an arch (4) is easy to turn and a structure can be secured when standing still, then a control circuit shown in FIG. 13 is unnecessary.

[0181] Namely, a control device (2 f) that is composed of a microcomputer, a data transmission network (100), an outside information input terminal (3 b), a shaft angle detection device (2 b), a plate angle detection device (1 f), a load transducer (1Q), an outside information output terminal (3 d), a friction material adjuster (1 t), a side to side adjustable motor (1 k), a motor (2 w), an arch upward supporting member (4 a), a motor (2 d), a transmission mechanism (2 g) and an oil pressure pump (2 e) that are shown in FIG. 13 aren't necessarily needed.

[0182] Simultaneously in the case to control the change of acceleration by making the gross touching area of a plate change and a touching pressure of the plate to a ground change, a friction material adjuster (1 t), a bottom opening (1 p) and friction material-supporting member (1R) that is concerned with the friction material (1 s) aren't needed.

[0183]FIG. 10 and FIG. 11 show the desirable caster for a robot of the other embodiment in this invention.

[0184] As shown in FIG. 10, a plate (10) is individually separated from a side supporting leg (12 a) and an upper supporting leg (12 b).

[0185] For this description the word “plate (10)” shall be used to mean “plate (10).”p The plate (10) is formed in the shape of a rectangle with the second up side flange cut off from a plate (1) and uses flexible materials such as plastic, metals such as aluminum and other materials.

[0186] This plate (10) assembles a first flange (10 a) so that the first flange is raised in a big bend radius (R) to roughly ⅓ of the entire length.

[0187] The first flange (10 a) is shaped so that it rises from a transit plane (g) with the touching part to the ground (10 b) of a plate (10) as starting point.

[0188] The plate (10) is sloped some degrees of an angle of inclination to the back (K) with the touching part to the ground (10 b) as a starting point.

[0189] The plate (10) is shaped approximately 10 cm in width, 20 cm in length and a 5 mm thick due to maintaining stable movement.

[0190] A hole (10 c) that is set up approximately in the center of the bottom of the plate (10) is set up like a wheel (2) that is assembled to rotate freely in the upper supporting leg (12 b) and which goes through the hole (10 c) where the wheel bottom meets a transit plane.

[0191] A wheel (2) shown in FIG. 10 of which the wheel bottom meets a transit plane is supported by both a side supporting leg (12 a) and an axle (2 a) of a wheel (2) at the back of the touching part to the ground (10 b) of a plate (10).

[0192] A side supporting leg (12 a), a wheel (2) and an axle (2 a) can assemble a motor, an engine and a drive mechanism such as a magnetic drive mechanism.

[0193] A supporting leg structure (12) shown in FIG. 10 is shaped by separating all of the side supporting leg (12 a), the upper supporting leg (12 b), the up-down adjustment screw (8), the resilient member (9), the first leg movement adjusting member (11 a), and the second leg movement adjusting member (11 b).

[0194] In other words, the side supporting leg (12 a) provides a mid-air structure in which a wheel (2) can be stored.

[0195] The side of the side supporting leg (12 a) is approximately rectangular and the tip of it makes a half-circle.

[0196] The side supporting leg (12 a) is shaped by a material that can support the load of an object such as a utensil or a structure by a plastic or metals and else.

[0197] The side supporting leg (12 a) is located on either side of an upper supporting leg (12 b) and is mounted over the top of an upper supporting leg (12 b).

[0198] A side supporting leg (12 a) and an upper supporting leg (12 b) are fixed by an up-down adjustment screw (8) and a resilient member (9).

[0199] An upper supporting leg (12 b) and a plate (10) are fixed by a first leg movement adjusting member (11 a) and a second leg movement adjusting member (11 b).

[0200] And a lower part of a rolling surface of a wheel (2) that went through a hole (10 c) opened in a plate (10) easily touches transit plane (g).

[0201] In the embodiment shown in FIG. 10, a plate (10) is fixed to the upper supporting leg (12 b) by both the first leg movement adjusting member (11 a) and the second leg movement adjusting member (11 b).

[0202] Both the side supporting leg (12 a) and the upper supporting leg (12 b) are shaped as one set to fix by an up-down adjustment screw (8) and a resilient member (9).

[0203] A plate (10) is attached to a front supporting leg (12 c) by a first leg movement adjusting member (11 a) and is attached to a rear supporting leg (12 d) by a second leg movement adjusting member (11 b).

[0204] A plate (10) arranges a hinge carrier (10 d) on a plate surface (10 e) in order to fix to the front supporting leg (12 c) by a first leg movement adjusting member (11 a).

[0205] A first leg movement adjusting member (11 a) is fixed to a hinge carrier (10 d) by using a shaft (13 a) of a hinge and a shaft stop (13 b) in order to fix to a plate (10) in a position of a hinge carrier (10 d) and the upper supporting leg (12 b) by the front supporting leg (12 c) and a first leg movement adjusting member (11 a).

[0206] The front supporting leg (12 c) and the first leg movement adjusting member (11 a) can be installed with control devices that use oil pressure, air pressure, water pressure, a spring, a wire, an electromotive or magnetic power.

[0207] A first leg movement adjusting member (11 a) can make a plate (10) adjustable in the front and back based on the movement of a plate (10) by an adjustment of a second leg movement adjusting member (11 b) from a hinge carrier (10 d) as the starting point.

[0208] A second leg movement adjusting member (11 b) is an up-down variable movement pressure device and is a control device in which oil pressure, air pressure, water pressure, a spring, a wire, an electromotive style and/or magnetic power is used.

[0209] The first leg movement adjusting member (11 a) and second leg movement adjusting member (11 b) could be an up-down variable movement pressure device and incorporates a pressure sensor.

[0210] When a second leg movement adjusting member (11 b) moves variably up and down, it enables a plate (10) to be moved variably to the front and back.

[0211] Therefore friction can be controlled by increasing or decreasing the amount of its gross area touching the ground when an end part (10 f) of a plate (10) touches the ground in a transit plane (g).

[0212] Therefore, it can brake without controlling the movement of a wheel by a brake that controls a wheel and/or an axle that holds a wheel of an existent caster.

[0213] In the embodiment shown in FIG. 10, a plate (10) is a complete unit with a second leg movement adjusting member (11 b) due to it being fixed to the rear supporting leg (12 d) by a second leg movement adjusting member (11 b).

[0214] However, a plate (10) can be also made as a separate structure from a second leg movement adjusting member (11 b).

[0215] When a plate (10) and a second leg movement adjusting member (11 b) were made separate components, a plate (10) and a second leg movement adjusting member (11 b) are fixed by means of a screw stop, glue and weld.

[0216] A first leg movement adjusting member (11 a) is fixed to a plate (10) by a hinge carrier (10 d) at a position of a hinge carrier (10 d) on a plate surface (10 e) in order to fix the upper supporting leg (12 b) by a front supporting leg (12 c) that has a structure of a hinge and a first leg movement adjusting member (11 a).

[0217] The front supporting leg (12 c) and a first leg movement adjusting member (11 a) can be installed with a control device that uses oil pressure, air pressure, water pressure, a spring, rubber, a wire, an electromotive style or magnetic power.

[0218] A wheel, whose bottom meets a transit plane from a hole of the plate, is fixed to a supporting leg structure rotating freely.

[0219] And the wheel, which is held by a supporting leg structure, can change an amount of a gross area touching the ground of a plate increase and decrease due to its up-down movement.

[0220] And also the wheel can assemble a drive mechanism.

[0221] Anything is good for the drive mechanism, such as an engine, a motor, a magnetic propulsion device or nuclear energy.

[0222] In the embodiment shown in FIG. 10, a plate (10) and a second leg movement adjusting member (11 b) are a complete unit.

[0223] And the friction can be controlled by a control device of a first leg movement adjusting member (11 a) and a second leg movement adjusting member (11 b), therefore, the friction can be adjusted, because of this means a side supporting leg (12 a), an upper supporting leg (12 b), a first leg movement adjusting member (11 a), an up-down adjustment screw (8) and a resilient member (9) are fixed respectively to each other.

[0224] A resilient member (9) of FIG. 10 is an adjustment material that can move a wheel (2) up and down properly, as illustrated and lies between the side supporting leg (12 a) and the upper supporting leg (12 b).

[0225] As for the embodiment, it is a rubber material that can be used as a shock absorber for the side supporting leg (12 a) and the upper supporting leg (12 b).

[0226] A resilient member (9) that consists of the rubber material can be made as a pressure device, such as air pressure or oil pressure.

[0227] The resilient member (9) could be made with an up-down variable movement pressure device, where a pressure sensor would be included.

[0228] The resilient member (9) could be made with a front and back variable movement pressure device, where a pressure sensor would be included at the same time.

[0229] The resilient member (9) can be shaped as a complete unit in either the side supporting leg (12 a) and the upper supporting leg (12 b).

[0230]FIG. 12 as shown is a general idea figure that shows a large wheel as compared to a caster for a robot traveling over obstacles.

Use possibility in industry

[0231] This invention is for a caster that has higher stability than the existent caster whose movement can be controlled without the use of a brake and is suitable for two pairs of feet in a walking robot.

[0232] This invention travels easier over obstacles than the existent caster and is suitable for indoor use, whereas an existent caster is limited by the size of a wheel. 

What is claimed is:
 1. A caster comprising: a plate adapted to touch the ground, said plate having a first upward curved end and a second upward curved end, said plate having an opening at a central position; a wheel and a support, said support rotatably supporting the wheel, said support having a shaft adapted to be connected to a device to be transferred; an arch member having a top portion, a first end, and a second end, said top portion being movably supported by the support at a position above the wheel, said first end being located between the first upward curved end and the opening, said second end being located between the second upward curved end and the opening; and a first socket and a second socket provided on the plate, said first socket receiving the first end of the arch member, said second socket receiving the second end of the arch member, wherein the first socket, the opening, and the second socket are aligned, and the wheel touches the ground through the opening, wherein (i) when the first upward curved end is detached from the ground, the wheel and the second upward curved end touch the ground, (ii) when the second upward curved end is detached from the ground, the wheel and the first upward curved end touch the ground, and (iii) when the first upward curved end and the second upward curved end touch the ground, the wheel touches the ground.
 2. The caster according to claim 1, wherein the plate has another opening where the first socket is positioned, and the caster further comprises a friction member provided at a bottom of the first socket, said friction member being adapted to touch the ground through the other opening.
 3. The caster according to claim 1, wherein the arch member pivots on a point where the top portion of the arch member and the support are connected.
 4. A caster comprising: a plate adapted to touch the ground, said plate having a front end and a rear end, said front end being upward curved, said plate having an opening at a central position; a wheel and a support, said support rotatably supporting the wheel, said support having a shaft adapted to be connected to a device to be transferred; a leg member having a top portion, a front leg end, and a rear leg end, said top portion being supported by the support at a position above the wheel, said front leg end being located between the front end of the plate and the opening, said rear leg end being located between the rear end of the plate and the opening; and a front socket and a rear socket provided on the plate, said front socket slidably receiving the front leg end, said rear socket slidably receiving the rear leg end, wherein the front socket, the opening, and the rear socket are aligned, and the wheel touches the ground through the opening, wherein (i) when the front end of the plate is detached from the ground, the wheel and the rear end of the plate touch the ground, (ii) when the rear end of the plate is detached from the ground, the wheel and the front end of the plate touch the ground, and (iii) when the front end and the rear end of the plate touch the ground, the wheel touches the ground. 